1. Field of the Invention
The present invention relates to an oil-in-water emulsion, in particular a transparent oil-in-water emulsion, the oil globules of which have a mean size of less than 100 nm, which comprises at least one silicone surfactant.
The present invention further relates to use of such an oil-in-water emulsion in topical application, in particular in the cosmetic and dermatological fields.
1. Discussion of the Background
Oil-in-water emulsions, wherein an oily phase is dispersed in an aqueous phase, are well-known in the field of cosmetics and in dermopharmaceuticals, in particular for the preparation of products such as lotions, skin tonics, serums, creams or eaux de toilette.
Emulsions comprising oil globules having a mean size of less than 100 nm are known as nanoemulsions. Such emulsions have been used to obtain transparent compositions having an appearance similar to that of water and resulting in a feel similar to that of a cream or a milk after application to the skin.
Thus, EP-A-406,162 describes nanoemulsions comprising an amphiphilic lipid phase comprising phosphoglycerides. These nanoemulsions are obtained by a high-pressure homogenization process. The nanoemulsions exhibit the disadvantage of being unstable on storage at conventional storage temperatures, i.e., between 0 and 45.degree. C., and for this reason provide yellow compositions producing rancid smells which develop after storage for a few days.
Moreover, EP-A-615,741 describes nanoemulsions comprising the combination of a long-chain fatty alcohol and/or fatty acid and a surfactant of the long-chain fatty acid soap type, forming a gel with a phase transition temperature greater than 60.degree. C. These nanoemulsions are prepared at high temperatures, greater than 70.degree. C., which makes it impossible to use heat-sensitive active principles (for example vitamins) in such compositions.
Accordingly, an object of the present invention is to provide a nanoemulsion which does not exhibit the disadvantages encountered with those known to date.
Yet another object of the invention is to provide a method for the cosmetic treatment of the skin, mucous membranes, nails, scalp, and/or hair.
Yet another object of the invention is to provide a method for the preparation of a composition intended for the dermatological treatment of diseases of the skin, mucous membranes, nails, scalp, and/or hair.
Yet another object of the invention is to provide a method for the therapeutic and/or non-therapeutic treatment of the skin, mucous membranes, nails, scalp, and/or hair.